Sum of an infinite geometric series with a common ratio of -1

Question

asked Mar 5, 2020 103k views

1 Answer

Tharanga Abeyseela · Answer 1 · 2020-03-09T06:03:35+0000

Hello from MrBillDoesMath!

Answer:

a/2

Discussion:

The question is a bit unclear but i think they are asking for the

sum (n = 1 to infinity) of a*r^n

where "a" is the first term of the series and "r" is the common ratio. Whne f = -1 the sum is

a/(1-r) = a/(1-(-1)) = a/(2)

Thank you,

MrB